high organic content (up to about 9 percent). Occasionally, the 

 cores were interf ingered with lenses of increased sand content, 

 especially those from areas adjacent to slopes. Carbonate content 

 increased seaward from basin to basin, with the increasing importance 

 of pelagic sedimentation in the form of foraminiferal tests. Carbonate 

 values averaged from less than 30 percent of the total sediment in 

 the Santa Cruz Basin to greater than 45 percent in the Tanner Basin. 

 Cohesion values for the sediment surface (0 to 30 cm) were lowest 

 in the Santa Cruz Basin (20 to 27 g/cm ) and highest, for basin sediments, 

 in the San Nicolas Basin (75 to 82 g/cm ) adjacent to the Santa Rosa- 

 Cortes Ridge. (It should be noted that cohesion values obtained 

 from these cores are questionable because 3 months lapsed before 

 tests were made, and some desiccation had taken place.) 



Sediments from the Santa Barbara Island slope (core 1 and grab 

 19) were greenish sandy muds. They represented a mixture of inorganic 

 shelf sands and silts with coarser shelf fragments and small pelagic 

 carbonate tests. The relative importance of organic remains was 

 evident since carbonate values in excess of 40 percent were obtained. 

 The greenish coloration of these 'sediments was due, at least in part, 

 to the presence of glauconite and biotite grains. A strength test 

 performed on core 1 resulted in a cohesion value of 44 g/cm . 



The coarsest sediments obtained were from the San Clemente Ridge 

 (cores 5 and 6) and the Santa Rosa-Cortes Ridge (core 11) . These 

 sediments may be classified texturally as sandy or gravelly muds 

 and muddy sands. Composition of these ridge sediments may be highly 

 variable depending on a specific locality. The coarse fractions 

 may include any or all of the following particles: organic fragments, 

 weathered rock fragments, mineral grains, or authigenic deposits. 

 Carbonate content varies widely with the relative importance of the 

 biogenic component. In line with the coarse character of the sediments, 

 strength values obtained for the San Clemente Ridge sediments were 

 high (about 237 g/cm ) . Core 11 was too short for reliable strength 

 tests. 



2. Bottom Photography . The distance covered on camera lowering 

 numbers 1, 2, 3, and 4, was 0.7, 0.5, 1.0, and 0.4 nautical miles, 

 respectively. In general, the bottom was uniform in composition 

 throughout each drift track. 



Camera lowering number 1 was taken on the San Nicolas slope toward 

 the Santa Cruz Basin in 850 meters of water. A sequential series 

 of six photographs from this lowering is presented in Figure 29. 

 At the onset of the camera lowering, fine grained sediments associated 

 with high organic debris dominated the area. Numerous animal tracks, 

 echinoderm spines, and holes made by burrowing organisms can be seen. 

 Approximately mid-way through lowering number 1, small nodules began 

 to appear. Emery (1960) has shown the area covered by lowering number 1 

 to be a probable location of phosphorite nodules. This appears to 



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